Stellarium is a free open source planetarium for your computer. It shows a realistic sky in 3D, just like what you see with the naked eye, binoculars or a telescope.It is being used in planetarium projectors. Just set your coordinates and go.

New in version 0.9.1

SKY* default catalogue of over 600,000 stars* extra catalogues with more than 210 million stars* asterisms and illustrations of the constellations* constellations for ten different cultures* images of nebulae (full Messier catalogue)* realistic Milky Way* very realistic atmosphere, sunrise and sunset* the planets and their satellites

Interface* a powerful zoom* time control* multilingual interface* scripting to record and play your own shows* fisheye projection for planetarium domes* spheric mirror projection for your own dome* graphical interface and extensive keyboard control* telescope control